In many medical procedures, such as balloon angioplasty and the like, it is known how to create an opening in a blood vessel, known as an arteriotomy, to allow for the insertion of various medical devices which can be navigated through the blood vessel to the site to be treated. Typically, the opening is formed in the femoral artery at a point proximate the groin and a series of medical devices are inserted in sequence. For example, a guide wire may first be inserted through the tissue tract created between the skin or the epidermis of the patient down through the subcutaneous tissue and into the opening formed in the blood vessel. The guide wire is then navigated through the blood vessel to the site of the occlusion, the heart, or any other area to be treated. Once the guide wire is in place, an introducer sheath can be slid over the guide wire to form a wider, more easily accessible, tract between the epidermis and the opening into the blood vessel If an angioplasty needs to be performed, the balloon catheter can then be introduced over the guide wire again through the introducer sheath, through the opening in the femoral artery, and then up the blood vessel to the site of the occlusion.
Once the procedure is performed, the guide wire, balloon catheter and any other equipment introduced can be retracted through the blood vessel, out through the opening in the blood vessel wall, out through the introducer sheath, and out of the body entirely The introducer sheath can then be removed and the physician or other medical technician is presented with the challenge of trying to close the opening both in the femoral artery and the tissue tract formed in the epidermis and subcutaneous tissue Most importantly, the opening in the blood vessel must be closed as soon as possible.
Over the years that these procedures have been performed, a number of apparatus and methods have been created for closing the opening in the blood vessel. Traditionally, and still commonly today, the opening is closed simply by the application of manual pressure. If sufficient pressure is applied, the blood vessel is constricted until a clot or thrombus forms whereupon the pressure can be removed and eventually the patient can become ambulatory once again. However, a number of drawbacks are associated with such a method For one, the process is very time consuming often taking many hours for the thrombus to fully form, during which time the patient is required to be stationary In addition, the mere application of such significant pressure to the groin is often quite uncomfortable for the patient.
In light of these difficulties, a number of proposals have been introduced to potentially alleviate such drawbacks In one approach, an anchor is inserted through the tissue tract and the blood vessel with a filament extending therefrom and connected to a sealing plug by a pulley arrangement. Once the anchor engages an interior surface of the blood vessel the filament can be used to pull the sealing plug securely into the tissue tract. While this approach does more quickly close the opening in the blood vessel than manual pressure application, it also results in the unfavorable characteristic of leaving a foreign body in the patient after the procedure is completed.
Another approach uses a resistive heating coil inserted into the opening in the blood vessel. Upon energization of the heating coil, the blood in the vicinity of the opening is caused to coagulate given the rise in temperature. This can be accomplished in combination with the introduction of a procoagulant into the site to again expedite the creation of the coagulation. While this approach has also met with some level of success, it also results in the introduction of a foreign body and/or substance into the tissue of the patient.
A still further approach involves the introduction of a collagen plug into the site of the opening. Such a plug is sized to be frictionally engaged by the sides of the opening in the blood vessel and thus held in place until coagulation of blood forms around the collagen plug The collagen plug is biodegradable and eventually is dispersed into the blood flow and eliminated from the body. However, just the introduction of such a foreign substance into the body can sometimes be, at the very least, inflammatory and uncomfortable for the patient.
In one collagen plug approach, a balloon catheter is inserted into the blood vessel, inflated, and then pulled back against an interior surface of the blood vessel wall to serve as a backstop. The collagen plug in such an approach is shaped and sized as to closely match the opening in the blood vessel wall and is pushed down into the tissue tract until it engages the inflated balloon. The inflated balloon can then be deflated and withdrawn leaving the collagen plug in place.
In another collagen plug approach, a delivery sheath wider than the opening in the blood vessel wall is used and then a collagen plug corresponding to the size of the inner diameter of the delivery sheath is pushed through the sheath so as to engage the outer surface of the blood vessel wall. The plug can then be tamped or compressed down against the exterior surface of the blood vessel wall such that a portion of the collagen extends into the opening of the blood vessel wall.
While each of the foregoing approaches have been met with some level of success, it can be seen that each also has substantial drawbacks. Accordingly, it would be advantageous for the art to provide an apparatus and method which can quickly close the opening in the blood vessel wall, forms a thrombus which reliably remains in place after formation, and minimizes patient discomfort.